﻿<!DOCTYPE html>
<html>
<head>
<meta name="viewport" content="width=device-width, initial-scale=1">
<title>Minimal GoJS Sample in Vue.js</title>
<meta name="description" content="Interactive diagram implemented by GoJS using Vue.js, including a diagram component and model binding." />
<!-- Copyright 1998-2019 by Northwoods Software Corporation. -->
<meta charset="UTF-8">
<script src="../release/go.js"></script>
<script src="../assets/js/goSamples.js"></script>  <!-- this is only for the GoJS Samples framework -->
<script src="https://unpkg.com/vue"></script>
<script id="code">
  function init() {
    if (window.goSamples) goSamples(); // init for these samples -- you don't need to call this

    var $ = go.GraphObject.make;

    Vue.component("diagram", {
      template: "<div></div>",  // just a plain DIV
      props: ["modelData"],  // accept model data as a parameter
      data: function() { return { diagram: null } },  // provide access to the GoJS Diagram
      mounted: function() {
        var self = this;
        var myDiagram =
          $(go.Diagram, this.$el,
            {
              layout: $(go.TreeLayout, { angle: 90, arrangement: go.TreeLayout.ArrangementHorizontal }),
              "undoManager.isEnabled": true,
              // Model ChangedEvents get passed up to component users
              "ModelChanged": function(e) { self.$emit("model-changed", e); },
              "ChangedSelection": function(e) { self.$emit("changed-selection", e); }
            });

        myDiagram.nodeTemplate =
          $(go.Node, "Auto",
          $(go.Shape,
            {
              fill: "white", strokeWidth: 0,
              portId: "", fromLinkable: true, toLinkable: true, cursor: "pointer"
            },
              new go.Binding("fill", "color")),
            $(go.TextBlock,
              { margin: 8, editable: true },
              new go.Binding("text").makeTwoWay())
          );

        myDiagram.linkTemplate =
          $(go.Link,
            { relinkableFrom: true, relinkableTo: true },
            $(go.Shape),
            $(go.Shape, { toArrow: "OpenTriangle" })
          );

        this.diagram = myDiagram;

        this.updateModel(this.modelData);
      },
      watch: {
        modelData: function(val) { this.updateModel(val); }
      },
      methods: {
        model: function() { return this.diagram.model; },
        updateModel: function(val) {
          // No GoJS transaction permitted when replacing Diagram.model.
          if (val instanceof go.Model) {
            this.diagram.model = val;
          } else {
            var m = new go.GraphLinksModel()
            if (val) {
              for (var p in val) {
                m[p] = val[p];
              }
            }
            this.diagram.model = m;
          }
        },
        updateDiagramFromData: function() {
          this.diagram.startTransaction();
          // This is very general but very inefficient.
          // It would be better to modify the diagramData data by calling
          // Model.setDataProperty or Model.addNodeData, et al.
          this.diagram.updateAllRelationshipsFromData();
          this.diagram.updateAllTargetBindings();
          this.diagram.commitTransaction("updated");
        }
      }
    })


    myApp = new Vue({
      el: "#sample",
      data: {
        diagramData: {  // passed to <diagram> as its modelData
          nodeDataArray: [
            { key: 1, text: "Alpha", color: "lightblue" },
            { key: 2, text: "Beta", color: "orange" },
            { key: 3, text: "Gamma", color: "lightgreen" },
            { key: 4, text: "Delta", color: "pink" }
          ],
          linkDataArray: [
            { from: 1, to: 2 },
            { from: 1, to: 3 },
            { from: 3, to: 4 }
          ]
        },
        currentNode: null,
        savedModelText: "",
        counter: 1,  // used by addNode
        counter2: 4  // used by modifyStuff
      },
      computed: {
        currentNodeText: {
          get: function() {
            var node = this.currentNode;
            if (node instanceof go.Node) {
              return node.data.text;
            } else {
              return "";
            }
          },
          set: function(val) {
            var node = this.currentNode;
            if (node instanceof go.Node) {
              var model = this.model();
              model.startTransaction();
              model.setDataProperty(node.data, "text", val);
              model.commitTransaction("edited text");
            }
          }
        }
      },
      methods: {
        // get access to the GoJS Model of the GoJS Diagram
        model: function() { return this.$refs.diag.model(); },

        // tell the GoJS Diagram to update based on the arbitrarily modified model data
        updateDiagramFromData: function() { this.$refs.diag.updateDiagramFromData(); },

        // this event listener is declared on the <diagram>
        modelChanged: function(e) {
          if (e.isTransactionFinished) {  // show the model data in the page's TextArea
            this.savedModelText = e.model.toJson();
          }
        },

        changedSelection: function(e) {
          var node = e.diagram.selection.first();
          if (node instanceof go.Node) {
            this.currentNode = node;
            this.currentNodeText = node.data.text;
          } else {
            this.currentNode = null;
            this.currentNodeText = "";
          }
        },

        // Here we modify the GoJS Diagram's Model using its methods,
        // which can be much more efficient than modifying some memory and asking
        // the GoJS Diagram to find differences and update accordingly.
        // Undo and Redo will work as expected.
        addNode: function() {
          var model = this.model();
          model.startTransaction();
          model.setDataProperty(model.findNodeDataForKey(4), "color", "purple");
          var data = { text: "NEW " + this.counter++, color: "yellow" };
          model.addNodeData(data);
          model.addLinkData({ from: 3, to: model.getKeyForNodeData(data) });
          model.commitTransaction("added Node and Link");
          // also manipulate the Diagram by changing its Diagram.selection collection
          var diagram = this.$refs.diag.diagram;
          diagram.select(diagram.findNodeForData(data));
        },

        // Here we modify VUE's view model directly, and
        // then ask the GoJS Diagram to update everything from the data.
        // This is less efficient than calling the appropriate GoJS Model methods.
        // NOTE: Undo will not be able to restore all of the state properly!!
        modifyStuff: function() {
          var data = this.diagramData;
          data.nodeDataArray[0].color = "red";
          // Note here that because we do not have the GoJS Model,
          // we cannot find out what values would be unique keys, for reference by the link data.
          data.nodeDataArray.push({ key: ++this.counter2, text: this.counter2.toString(), color: "orange" });
          data.linkDataArray.push({ from: 2, to: this.counter2 });
          this.updateDiagramFromData();
        }
      }
    })
  }
</script>
</head>
<body onload="init()">
  <div id="sample">
    <diagram ref="diag"
             v-bind:model-data="diagramData"
             v-on:model-changed="modelChanged"
             v-on:changed-selection="changedSelection"
             style="border: solid 1px black; width:100%; height:400px"></diagram>
    <button v-on:click="addNode">Add Child to Gamma</button>
    <button v-on:click="modifyStuff">Modify view model data without undo</button>
    <br/>Current Node:
    <input v-model.lazy="currentNodeText" v-bind:disabled="currentNode === null"/>
    <br/>The saved GoJS Model:
    <textarea style="width:100%;height:250px">{{ savedModelText }}</textarea>
    <p class="box bg-info">
      This is a <a href="https://vuejs.org">Vue.js</a> sample.
    </p>
    <p>
      The GoJS Diagram is held in a "diagram" component, and only exposes a small fraction of the functionality of <a>Diagram</a>.
      That includes the "modelData" property, to initialize the Diagram to show a model, and
      the "diagram" property, to get access to the <a>Diagram</a>.
    </p>
    <p>
      That component also raises two events: "model-changed" corresponding to <a>Model.addChangedListener</a>, and
      "changed-selection" for the "ChangedSelection" <a>DiagramEvent</a>.
    </p>
    <p>
      That component also supports two different ways of modifying the diagram: access to the <a>Model</a> via the "model" method
      so that code can call Model methods such as <a>Model.setDataProperty</a>, and an "updateDiagramFromData" method.
      The latter permits data changes without calling Model methods to notify Diagrams showing the model,
      but at the cost of not being able to support undo and redo.
    </p>
  </div>
</body>
</html>